The Paralysis Tick

Apart from fleas, the paralysis tick (Ixodes Holocyclus) is the most significant external parasite domestic animals, their owners and their vets encounter, especially around spring/summer. It occurs in the coastal areas of Eastern Australia and is usually found on wildlife such as bandicoots, possums and wombats.

Tick paralysis occurs most commonly in dogs, though all warm-blooded animals, including humans, can be affected by the neurotoxin produced in the saliva of the tick. The tick attaches to these animals (to feed on their blood) in the final stages of its life-cycle, the female needing to engorge with blood before she can lay eggs (2000-3000 at a time.) After engorgement, which takes 4-7 days, the tick will drop off the animal.

Tick Paralysis: Signs

Clinical signs, due to the neurotoxin, can begin within a couple of days of attachment of the tick, and include the following:

  • Hoarse voice
  • Increased salivation / “frothing” at the mouth
  • Dilated pupils
  • Increased respiratory effort seen as slowed and more pronounced breathing, often with a characteristic grunting sound
  • Wobbliness then paralysis of hind limbs and eventually four limbs

Death will occur due to respiratory failure, or can occur due to secondary pneumonia, due to “breathing down” saliva, food and water because of paralysis of their swallowing muscles.

Stages

A scale of stages 1-5 of tick paralysis is used to describe the degree to which the tick toxin affects an animal, as follows:

Stage 1 The mildest from, generally seen as a “wobble” or “weakness” in the hind limbs, with maybe a changed bark in the case of the dog.
Stage 2 Includes hind limb paralysis, the animal is able to sit up on its front legs, but can’t stand up on the back ones.
Stage 3 The ascending paralysis continues to affect the front legs and at this stage the animal can lie on its chest, but is not able to hold itself up with front or hind limbs.
Stage 4 The animal can only lie on its side, is unable to hold itself or right itself to lie on its chest, and is suffering from marked breathing difficulty /increased effort.
Stage 5 Respiratory failure is occurring and death is imminent

Treatment

Variations in the number of signs, which occur, appear and the severity with which they affect an individual may occur, and depend on factors such as the number of ticks on the animal and any history of recent exposure to ticks. Because of these factors, no hard and fast rules can be made regarding how soon veterinary treatment should be sought, particularly during stage 1 of the tick paralysis syndrome. However we encourage you to follow these guidelines:

  • Step 1 If your pet shows any of the above signs, search him/her thoroughly for ticks. Please note: ticks can be very difficult to find and can be anywhere on the body, but tend to favour the head and especially under any collars! They can vary in size from a match-head to a thumbnail size according to how long they have been engorging with blood. If you can’t find a tick, go to step 3.
  • Step 2 If you do find one or more ticks, remove it but keep looking. Removal is best achieved by firmly grasping the tick with your fingers, or a blunt-ended tweezers, as close to the animal’s skin as possible and pulling straight out with a single sharp, strong movement. Aggravation of the tick through rotation, or application of metho, kero etc simply induces the tick to inject more saliva and therefore toxin into your animal.
  • Step 3 Keep any animal suspected of suffering any degree of tick paralysis quiet and cool. Do not place him/her out in the sun, wrapped in blankets or in front of the fire! This tends to make the signs worse. Keep searching for more ticks!
  • Step 4 Do not give any food! Only offer fluids to those animals not apparently affected at the front end and only offer small amounts at a time and if any coughing, retching or vomiting occurs do not offer anything by mouth at all. Keep searching for ticks!
  • Step 5 DEFINITELY contact your local vet if your animal has progressed to stage 2 or more ASAP
  • Step 6 In some cases, if a tick is removed when the animal is only slightly affected i.e. in stage 1 they may not get any worse, particularly if they have had ticks on them before and haven’t been affected, and if steps 1 to 3 are followed.

HOWEVER, BE WARNED. Although your animal may appear to be only slightly affected at the time of tick removal, progression of signs can occur from up to 24 hours after tick removal and what began as a slight wobble in the back legs and a funny voice, can become complete paralysis and severe respiratory distress overnight or during the day.

There is no doubt at all, that the sooner ticks are removed and the earlier the treatment is commenced the better the rate of recovery.

Veterinary treatment of tick paralysis involves primarily the intravenous administration of tick antivenene. Treatment also involves the administration of a mild sedative (stress is a major factor contributing to the severity of signs, especially in cats). Antibiotics (to aid in the prevention of secondary pneumonia developing) and subcutaneous fluids to maintain hydration of the animal.

Obviously, for proper treatment hospitalisation of your animal is required until he/she is able to walk around, eat and drink with no problems. If treatment is given in the early stages of tick paralysis, the shorter the stay in hospital: often only one night is required for stages 1-2.

Prevention

From the above, it is obvious that prevention is far better than cure for all concerned. While it is impossible to obtain 100% protection for your animal from tick paralysis, if you are in tick area, it is very possible to minimise the risks. The best method and one which should never be entirely replaced, is checking your pet regularly – preferably daily. Running your fingers all over the animal, against the direction of hair growth, making sure you go down to the skin, in between the toes, under the collar, around the eyes, in and around the ears, and everywhere in between and beyond, (including the tip of the tail!), is an excellent habit to get into. Due to the difficulty in finding the very small ticks, even some of the bigger ones, and the practicality of this occurring daily in some situations, there are a number of products to be
used in conjunction with tick searches.

Come into either of our clinics to discuss what the best prevention product we have available for your pet.